I don't think a lot of thought is put into it. It's inertia and 'what the the other successful big companies do'. There is also a subset that enjoys leetcode

I don't think a lot of thought is put into it. It's inertia and 'what the the other successful big companies do'. There is also a subset that enjoys leetcode interviews and complain if you don't do it. Everyone does it because big daddy successful google started it, and thus it self perpetuates. 20 years ago it was bullshit microsoft-style lateral thinking questions that were that generation's leetcode. On top of that, the only people who can really get rid of leetcode are pretty much sr staff or principle engineers and high level HR people. It also doesn't get you promoted or paid more in most companies to go on a long project to change the interview process. Thus it doesn't get changed. I estimate that leetcode will probably go away in many big companies in 5-15 years from now as today's sr engineers become the next sr management and founders that actually makes these decisions. Many startups today explicitly do not have leetcode interview loops, while 10 years ago many did have leetcode interview loops. When that generation of startups have their facebook that defines their decade and thus defines the next common interview fad, leetcode will start going away. It also allows you have any engineer interview pretty much any other engineer, which makes interviews overall easier to do.